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ELI5 Yahaaa

Under the floor and back

Where Do Escalator Steps Go at the Top?

Escalator steps run on a closed chain, flattening at each end and returning underneath.

Steps rise, flat and level They flattenat the top They travel back underneath And come upagain as newstepsLoop
The steps never end. They go under and come back.

  1. Step 1 of 5

    The steps are one continuous loop.

    Every step is on achainThe chain is a closedloopSteps return underneathNone are added orremoved

    Every step is bolted to the same chain, and that chain is a closed ring. Nothing is ever added at the bottom or removed at the top.

  2. Step 2 of 5

    Each step rides on two sets of wheels.

    One step Two axles on two tracks

    One axle sits near the front of the step and another near the back, and each axle runs along its own separate guide track.

  3. Step 3 of 5

    Changing the track spacing tilts the step.

    Front wheels on onetrackset the frontheightBack wheels on anotherset the backheightSpacing changes alongthe runso the steptilts orflattens

    Because the front and back wheels are guided independently, pulling the two tracks closer or further apart changes the angle the step sits at.

  4. Step 4 of 5

    At each end the tracks converge.

    1 Mid-flight — afull stairshape2 Near the top —tracks converge3 At the comb —perfectly flat

    Approaching the comb plate the two tracks come level with each other, so every step folds down into a flat platform just before you step off.

  5. Step 5 of 5

    Then they travel back, out of sight.

    Steps pass underthe floor plate Carried back downinside

    Flattened steps slide under the floor plate and are carried down the inside of the machine, ready to be tilted back into stairs at the bottom.

    A shopping-centre escalator runs at about half a metre per second, which works out at roughly 6,000 people an hour.

The short version

Escalator steps run on a closed chain, and two guide tracks at changing spacings make them form stairs in the middle and flatten at both ends.

Try it yourself

Watch the comb plate at the top of an escalator. Each step visibly sinks flat before it slides away out of sight.

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